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This is, perhaps, as good a place as any to call attention 

 to some points, regarding American species, before passing 

 on to those of foreign origin. The effect of civilization upon 

 insectivorous vertebrates, like birds, has had a very decided 

 effect upon our insect fauna, as no one can deny, but we 

 find ourselves well nigh helpless when we come to attempt 

 to measure the extent of this influence. The effect of the 

 interpolation of outside species, into the fauna of Ohio, has 

 most assuredly affected species other than those incoming, 

 or such as they have jostled, so to speak, in their progress. It 

 is not difficult to see that some of the parasites and preda- 

 cious enemies of species fast becoming extinct, might, with- 

 out great effort add some of the new comers to their bill of 

 fare, and thus be able to sustain their place in the insect 

 fauna. Then, some of these migrants may have brought 

 their own parasitic enemies with them, and added these as 

 well as themselves to our fauna. I have already observed 

 Podisus spinisus Dallas, which occurs generally in the United 

 States, attacking adults of Murgantia Jiistrionica in Ohio. 

 Then there are the parasites of such species as are becoming 

 extinct, or too rare to support any considerable number of 

 natural enemies, not only primary and secondary, but tertiary 

 as well, all of which must feel the effects of this upsetting of 

 the natural order of things. It is almost as if one were to 

 drop a shower of pebbles into the surface of a small lake, 

 and attempt to follow out the movement and course of 

 every ripple. Finally, what is to be the effect of this con- 

 tinual effort toward a readjustment of things? What effect 

 will all these changes of environment, geographical and 

 meteorological conditions, food habits and altered modes of 

 living have upon these species most mfluenced? Will not, 

 in some cases at least, characters now considered specific, 

 gradually become obsolete, and others, more recently ac- 

 quired, take their places? It looks to me as though nearly 

 all of the important biographical problems of today would 



